On Thu, Dec 14, 2017 at 10:53 PM, Bob kb8tq wrote:
>
>
> Of course this *assumes* an electronic approach. Given that it’s moving
> pretty slow and you
> only are looking at fractions of a millisecond, one *could* do an electro
> mechanical design …...
>
> Bob
>
> There is
I have a few questions about your setup:
(1) What is the waveform shape you are measuring? Are you measuring a
square wave (or some other duty cycle waveform with fast rise and
falling edges)? Or is it a sinewave with low harmonic content?
(2) How is the counter voltage threshold set with respect
Hi
My guess is that the “best design” would likely do a sample at some specific
time of day.
Just when would depend a bit on your local grid and how it is fed and loaded.
There are
definitely “it’s 6 PM and everybody just got home” issues with power line
phase.
Next question wold be how long
t...@leapsecond.com said:
> For GPS and OCXO the choice of time constant is fairly obvious. But the
> ADEV for mains frequency isn't quite as pretty. So I'm not sure several
> hours would work; maybe more like days or weeks? Here's a sample ADEV for
> power line frequency:
Has anybody
On Thu, December 14, 2017 8:39 pm, Tom Van Baak wrote:
> One can determine the appropriate time constant by looking at the ADEV of
> the two clocks
It appears that the appropriate design would use a local oscillator which
is stable to better than 10^-7 at 5 years and approximately 1200 days time
Here is a project which mixed the Time Kube IF output back to 10 MHz for
use as a frequency (not time)
standard:http://schematicsforfree.com/archive/file/Oscillators%20and%20Generators/Misc/10Mhz%20Frequency%20Standard%20Using%20Wwv.pdf
I believe that the Time Kube uses a 3-transistor mixer / 455
That’s not a problem, that means you’re phase locked instead of just frequency
locked.
This is the phase-nuts mailing list, right? :-)
Tim N3QE
> On Dec 14, 2017, at 6:19 PM, Alan Melia wrote:
>
> I dont think working that way would give a stable clock in the UK.
I dont think working that way would give a stable clock in the UK. Our
frequency can vary more than the US but the number of cycles between 0800 on
one day and the next is mandated to be correct (I presume +/- 25 :-)) ). So
you would be chasing a moving target, and at no time of the day need
Well, I had a cable jump out of a switch yesterday, which took 10 s to
fix when home. Ah well. A more robust setup is in the making.
Cheers,
Magnus
On 12/14/2017 08:02 AM, Ulf Kylenfall via time-nuts wrote:
Tried to mail the pictures to Magnus. The mail bounced back.
Ole Petter Ronningen
Since the power line has the desired long term stability but is poor on the
short term, I wonder if a solution might be to use it as the reference for
a "power line disciplined oscillator."
You would want a filter time constant of several hours in the control loop
to smooth out the variations in
apollo...@gmail.com said:
> Want to provide an accurate (relatively accurate) 60 hz reference to the
> chip. Some room inside for custom modifications. Does a TCXO or similar
> exist in a small package that provides 60 hz ticks?
I doubt if you will find a TCXO that puts out 60 Hz. But it's
National Semi used to make a chip (MM5369) that was designed specifically
for that task, but it's long out of production. I don't know of any
off-the -shelf 60Hz generators, but it's pretty easy to build one.
Here are a couple of web pages that will generate a 60Hz crystal controlled
signal.
Pat,
> They drift a few seconds in the course of a few days, and wander back and
> forth.
Yes, it's normal for AC mains to drift around by a few seconds over a day but
it usually stays roughly on-time over weeks and months. Here's an old example
of monitoring mains time & frequency for 45
PIcked up a couple of large size Radio Shack 63-960 LED clocks with
Settable alarm, at local Goodwill store. $3.00 ea work great see across
room, loud Alarm, etc...
Barely missed, by seconds, getting a classic Hallicrafters General coverage
receiver
(not like say, S-38) but a larger light
Seconded on the Andy Talbot suggestion, iirc he has almost exactly what you
need
On 14 Dec 2017 17:19, "Dave B via time-nuts" wrote:
> Take a look at Andy Talbot's page at...
>
> http://www.g4jnt.com/Synthesizers.htm
>
> Lots of good options there for that sort of thing.
>
>
Take a look at Andy Talbot's page at...
http://www.g4jnt.com/Synthesizers.htm
Lots of good options there for that sort of thing.
73.
Dave G0WBX.
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The problem with the 9854 DDS is that the analog reconstruction filters that you have to place after its outputs, are
not guaranteed to have
*exactly* the same phase behavior between the two sections (I and Q). This may or may not be important, depending on
the application.
For sure, for an
I have those 9954/9854 boards and the problem is the drivers for newer
operating systems past XP aren’t available. The AD9854/9954 boards were clones
of the AD eval kits and you downloaded the eval kit software from AD. I got
the board(s) working with Windows 7 but it took a lot of screwing
Bascom is a Basic compiler, for AVR chips if my memory serves right.
> On Dec 13, 2017, at 12:10 PM, Adrian Godwin wrote:
>
> Maybe this one ?
>
> http://www.qsl.net/pa3ckr/bascom%20and%20avr/ad9951/index.html
Nigel
The link to Siemens came from Companies House searches on the name.
They reference the link to Siemens and mention Christchurch as a base
(however that could just have been a registered office for accounting
purposes and not the engineering / production location).
I have several model 100
Rick
Please contact me off list we did a board for Corby to be used with the HP Rb
using a PIC but I would have to better understand your needs to figure out what
board to use.
Bert Kehren
In a message dated 12/13/2017 4:06:01 PM Eastern Standard Time,
artgod...@gmail.com writes:
It's a
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